Angle drive with power distribution

ABSTRACT

An angle drive having a housing ( 11 ) with a first axis (A 1 ) for bearing means and a second axis (A 2 ) for bearing means, which latter axis (A 2 ) intersects the first axis (A 1 ) at right angles, having an input shaft  16  which is supported in the housing, which carries an input ring gear ( 19 ) and is positioned on the first axis (A 1 ), having an output shaft ( 28 ) which is supported in the housing, which carries an output gearwheel ( 27 ) and is positioned on the second axis (A 2 ), having a counter ring gear  20  which is supported in the housing, which is positioned on the first axis (A 1 ) and which, with reference to the second axis (A 2 ) is arranged and designed symmetrically relative to the input ring gear ( 19 ), having at least one intermediate gearwheel which is supported in the housing, which is arranged on an axis (A 3 , A 4 ) positioned radially relative to the first axis (A 1 ) and in one plane together with the second axis (A 2 ) and which is provided with the same type of toothing as the output gearwheel ( 27 ). The counter ring rear ( 20 ) is supported so as to be independently rotatable relative to the input ring rear ( 19 ). The input ring gear ( 19 ) and the counter ring gear ( 20 ), via their respective teeth, simultaneously engage the output gearwheel ( 27 ) and the at least one intermediate gearwheel.

The invention relates to an angle drive having a housing with a firstaxis A₁ for bearing means and a second axis A₂ for bearing means, whichlatter axis A₂ intersects the first axis A₁ at right angles, having aninput shaft which is supported in the housing, which carries an inputring gear and is positioned on the first axis A₁, having an outputshaft, which carries an output gearwheel and is positioned on the secondaxis A₂. Angle drives can be used in many ways in motor vehicles, landmachinery and machines tools, just to mention a few applicationexamples. In the field of motor vehicle technology, they are required infour wheel drive vehicles with transversely built-in front engines. As arule, such vehicles are derived from basic models with a front wheeldrive only. In such cases, the angle drive directly follows adifferential drive of the front axle, with the input shaft of the angledrive being firmly coupled to the differential carrier of thedifferential drive. The input shaft of the angle drive is provided inthe form of a hollow shaft through which one of the sideshafts of thedifferential drive leads to the front axle drive.

The installation space of the angle drive to be accommodated in this waybetween the front axle differential and a drive-shaft behind orunderneath the combustion engine is naturally very limited. Because ofan ever increasing use of diesel engines with a high torque, thepreviously used angle drives reach their performance limit, i.e. inmaximum torque test runs, the required service life is no longerreached. Because of the limited installation space, the size of theangle drive cannot be increased, and it has to be taken into accountthat the transferable torque of angle drives is primarily determined bythe ring gear diameter which cannot be increased.

It is the object of the invention to propose an angle drive, especiallyfor said preferred application, which comprises a higher torque capacityin a given installation space, especially with a limited diameterdimension.

For this purpose, there is provided an angle drive with the followingcharacteristics:

-   having a counter ring gear which is supported in the housing, which    is positioned on the first axis A₁ and which, with reference to the    second axis A₂, is arranged and designed symmetrically relative to    the input ring gear (large gearwheels),-   having at least one intermediate gearwheel which is supported in the    housing, which is arranged on an axis A₃, A₄ positioned radially    relative to the first axis A₁ and in one plane together with the    second axis A₂ and which is provided with the same type of toothing    as the output gearwheel (pinions),-   the counter ring gear is supported so as to be independently    rotatable relative to the input ring gear,-   the input ring gear and the counter ring gear (large gear-wheels),    via their respective teeth, simultaneously engage the output    gearwheel and the at least one intermediate gearwheel (pinions).

In said angle drive, the above means achieve a power distribution which,because the output gearwheel is engaged twice, i.e. by the input ringgear on the one hand and by the counter ring gear on the other hand,leads to the tooth forces at the former being halved. The input ringgear and the counter ring gear which, substantially, are of identicaldesign, are subjected substantially to the same loads. Because theysimultaneously engage the output gearwheel and the at least oneintermediate gearwheel, their tooth forces are at least halved.

By halving or dividing into three the tooth forces with a given ringgear diameter, with an unchanged toothing shape and the same toothstrength, the transferable torque can ideally be doubled. In this way,by using high-torque diesel engines, the problems existing in connectionwith angle drives are solved completely. The invention allows a largering gear at the differential carrier to be replaced by smaller ringgears in the form of an input gearwheel and a counter gearwheel.

Independently of the preferred application mentioned here, an angledrive with power distribution of said type can also be used incombination with a rear axle differential. When the vehicle is drivingforward, the torque flow can take place from the shaft so far referredto as output shaft to the shaft so far referred to as input shaft. Thisalso applies to other applications.

According to a first preferred embodiment, a single intermediategearwheel is supported co-axially relative to the second axis A₂.According to a further embodiment it is proposed that several,especially two intermediate gearwheels, by means of their radial axesA₃, A₄, form identical pitch angles with the second axis A₂.

Furthermore, it is proposed that the input shaft is a hollow shaftthrough which a through-shaft is able to pass; that the input shaft issupported twice in the housing; that the input ring gear and the counterring gear on the input shaft are floatingly supported in the housing;that the counter ring gear is supported on the input shaft by means of aradial bearing; that the counter ring gear is axially supported on theinput shaft by means of an axial bearing; that the output shaft issupported once in the housing; and that at least one intermediategearwheel is rotatably supported on a fixed housing journal.Furthermore, it is possible that the input ring gear and the counterring gear are crown wheels and that the output gearwheel and the atleast one intermediate gearwheel are spur gears with straight toothingor helical toothing. The toothings can also be provided in the form ofspiral toothings or as helical toothings at the input ring gear and atthe counter ring gear and, accordingly, in the form of spiral orstraight or helical toothings at the output gearwheel and at theintermediate gearwheels. Further possibilities consist in that the inputshaft is axially floatingly supported in the housing and that there isarranged a plug-in sleeve in the journal end of the input shaft for thepurpose of being connected to an output shaft of a differential.

By supporting the input ring gear and the counter ring gear on the inputshaft, the housing is kept completely free from axial forces in thedirection of the first axis A_(n). If the toothing is selected in theform of crown wheels or straight spur gears, the output shaft, too, iskept completely free from forces extending in the direction of the axisA₂. Because of being engaged twice, i.e. by the input ring gear and bythe counter ring gear, the output gearwheel is held so as to be centredbetween same, so that no radial bearing forces can occur at the outputshaft itself. This means that, as compared to simple prior art angledrives, the load on the housing is reduced considerably, so thatmaterial savings could be possible. Furthermore, by providing the ringgearwheels in the form of crown wheels and the output and intermediategearwheels in the form of straight pinions, the assembly procedure issimplified because the pinions can move radially towards the crownwheels without there occurring any change in the type of engagement. Therequirements in respect of the accuracy of the axial position of theoutput gear and of the intermediate gears with reference to axes A₂, A₃and A₄ are thus reduced.

The above-mentioned measures, which lead to the load on the housingbeing reduced, simultaneously cause the shafts and gearwheels to beacoustically uncoupled from the housing. This is an advantageous sideeffect with occurs automatically in the angle drive in accordance withthe invention.

Two preferred embodiments of the invention are illustrated in thedrawings and will be described below.

FIG. 1 shows an inventive drive in a section through the input shaft andthe output shaft in a first embodiment.

FIG. 2 shows the drive according to FIG. 1 in a section expendingperpendicularly relative to the input shaft through the output shaft.

FIG. 3 shows an inventive drive in a section through the input shaft andthe output shaft in a second embodiment.

FIG. 4 shows the drive according to FIG. 3 in a section extendingperpendicularly relative to the input shaft through the output shaft.

Below, FIGS. 1 and 2 will be described jointly. The housing 11 of anangle drive comprises a flange sleeve 12 with a threaded flange 13having a first axis A₁, by means of which the angle drive can be flangedto a differential drive for example, as a well as a cover 14 positionedopposite the threaded flange 13. At the drive housing 11, there isformed on a housing sleeve 15, whose axis A₂ is aligned radiallyrelative to the axis A₁ of the flange sleeve 12. An input shaft 16having an axis A₁ and carrying an input ring gear 19 is floatinglysupported by two ball bearings 17, 18 in the drive housing. The inputring gear is positioned on a seat face 21 of the input shaft 16 and isaxially supported on a collar 22 to which it is welded. A counter ringgear 20 having the same type of toothing and the same size as the inputring gear 19 is positioned symmetrically relative to the latter. Thecounter ring gear 20 is freely rotatably supported on the input shaft 16via a radial bearing 23 and is supported on the input shaft 16 via anaxial bearing 24, a disc 25 and a securing ring 26. The input ring gear19 and the counter ring gear 20 are provided in the form of crownwheels. Both engage an output gearwheel 27 which is formed so as to beintegral with an output shaft journal 28. Said output gearwheel 27 isprovided in the form of a straight spur gear. The output shaft journal28 is supported via a ball bearing 29 in the sleeve projection 15. Theoutput gearwheel 27 engages the input ring gear 19 and the counter ringgear 20, and this also applies to two intermediate gearwheels 31, 32which also comprise axes A₃, A₄ which are aligned radially relative tothe first axis A₁ and which are positioned in the same plane as thesecond axis A₂. Die intermediate gearwheels 31, 32 run via needlebearings 49, 50 on rotary journals 33, 34 which are supported in acarrier structure 35 bolted into the housing 11 by means of bolts 36,37. A connecting flange 38 is fixed by means of a disc 40 and a bolt anda bolt 41 to the end of the shaft journal 28, with the shaft journal 28and the connecting flange 38 engaging one another by means of a shafttoothing 39. The input shaft 16 is sealed by a seal 42 relative to thethreaded flange 13 and sealed by a seal 43 relative to the cover 14.Furthermore, the output shaft 28 is sealed by a seal 44 relative to thesleeve projection 15. The input shaft 16 is provided in the form of ahollow shaft, with a through-shaft 45 passing through said input shaft16. The through-shaft 45 is sealed by a seal 46 relative to the inputshaft 16. The torque introduced via the input shaft 16 is completelyuniformly distributed via the intermediate gearwheels 31, 32 to the tworing gears 19, 20. The tooth forces at the ring gears 19, 20 areaccommodated in the form of internal forces by the input shaft 16. Thehousing 11 remains completely free from axial loads in the direction ofthe axis A₁ through the input shaft 16. The ring gears 19, 20 which arefloatingly arranged on the input shaft 16 are held and centred as aresult of the symmetric arrangement of the gearwheels 27, 31, 32, sothat no radial forces of any worthwhile values reach the housing 11 fromthe input shaft 16. The output gearwheel 27 is centred between the ringgears 19, 20, so that the shaft journal 28 is not subjected to anybending forces. As a result of the tooth shape (straight-toothedpinions) and the double engagement with the ring gears 19, 20, theoutput gear 27 and the bearing of the output shaft journal 28 are notsubjected to axial forces either.

FIGS. 3 and 4 will be described jointly below. A housing 51 of an angledrive is bolted to a flange sleeve 52 which is provided with a threadedflange 53 which comprises a first axis A₁ and by means of which theangle drive can be flanged to a differential drive for example, as wellas with a cover 54 arranged opposite the flange 52. At the drive housing51, there is flanged on a housing sleeve 55 whose axis A₂ is alignedradially relative to the axis A₁. The annular drive housing 51, via asingle radial spoke 88, holds a hub 87 which extends coaxially relativeto the axis A₁. An input shaft 56 with an axis A₁ is supported in saidhub 87 by means of a radial bearing 57. On one side of the bearingregion, the input shaft 56 carries an input ring gear 59 which ispositioned on a seat face 61 of the input shaft 56 and is axiallysupported on a collar 62 to which it is welded. On the other side of thebearing region and symmetrically relative to the input ring gear 59,there is positioned a counter ring gear 60 with the same tooth formationand the same size. The counter ring gear 60 is freely rotatablysupported on the input shaft 56 by means of a radial bearing 63 and issupported on the input shaft by means of an axial bearing 64, a disc 65and a securing ring 66. The input ring gear 59 and the counter ring gear60 are provided in the form of crown wheels. Both engage an outputgearwheel 67 which is formed so as to be integral with an output shaftjournal 68. Said output gearwheel 67 is a straight spur gear. The outputshaft journal 68 is supported by a ball bearing 69 in the sleeveprojection 55. The output gearwheel 67 engages the input ring gear 59and the counter ring gear 60, and this also applies to two intermediategear-wheels 71, 72 which also comprise axes A₃, A₄ which are alignedradially relative to the first axis A₁ and which are positioned in thesame plane as the second axis A₂. The intermediate gearwheels 71, 72 runon rotary journals 73, 74 which are supported on the radial outside inthe housing 51 and on the radial inside in the hub 83. The rotaryjournals are secured by securing rings 95, 96 and sealed by O-rings 97,98. The intermediate gearwheels 71, 72 are supported on needle bearings89, 90. The input shaft 56 is connected to a plug-in sleeve 99 via ashaft toothing 100. The input shaft 56 with the plug-in sleeve 99 isprovided in the form of a hollow shaft, with a through-shaft 85 passingthrough same. The input shaft is sealed by a seal 83 relative to thecover 54 and the through-shaft 85 is sealed by a seal 86 relative to theinput shaft 56. A connecting flange 78 is fixed by a disc 80 and a bolt81 to the end of the output shaft 68. The shaft journal 68 and theconnecting flange 78 are secured against rotation by a shaft toothing79. Furthermore, the output shaft 68 is sealed by a seal 84 relative tothe sleeve 55. The torque introduced via the input shaft 56 iscompletely uniformly distributed via the intermediate gearwheels 71, 72to the two ring gears 59, 60. The tooth forces at the ring gears 59, 60are accommodated in the form of internal forces within the input shaft16 and hold the annular housing 51 completely free from axial loads inthe direction of the axis A₁. Furthermore, the axially floatinglyarranged input shaft 56 is held and centred as a result of the symmetricarrangement of the gear-wheels 67, 71, 72, so that no radial forces ofany worthwhile values reach the housing 51 from the input shaft 56. Theoutput gearwheel 67 is centred between the ring gears 59, 60, so thatthe shaft journal 68 is not subjected to any bending forces. As a resultof the tooth shape (straight-toothed pinion) and the double engagementwith the ring gears 59, 60, the output gear 67 and the bearing 69 of theoutput shaft journal 28 are not subjected to axial forces either.

1. An angle drive comprising: a housing; an input shaft which issupported in the housing and is positioned on a first axis (A₁); aninput ring gear fixed on the input shaft; an output shaft which issupported in the housing, and which carries an output gearwheel and ispositioned on a second axis (A₂) which intersects the first axis (A₁) ata right angle; a counter ring gear which is supported in the housing,which is positioned on the input shaft and which, with reference to thesecond axis (A₂), is arranged and designed symmetrically relative to theinput ring gear; and at least one intermediate gearwheel which issupported in the housing, which is arranged on an axis (A₃, A₄)positioned radially relative to the first axis (A₁) and in the sameplane with the second axis (A₂) and which is provided with the same typeof toothing as the output gearwheel; wherein the counter ring gear issupported so as to be independently rotatable relative to the input ringgear, and wherein the input ring gear and the counter ring gear, viatheir respective teeth, simultaneously engage the output gearwheel andthe at least one intermediate gearwheel, and wherein the input shaft isaxially floatingly supported in the housing.
 2. (canceled)
 3. An angledrive according to claim 1, wherein several intermediate gearwheels, byway of respective radial axes (A₃, A₄), form identical pitch angles withthe second axis (A₂).
 4. An angle drive according to claim 1 wherein theinput shaft is a hollow shaft adapted to receive a through-shaft.
 5. Anangle drive according to claim 1 wherein the input shaft is supportedtwice in the housing.
 6. An angle drive according to claim 1 wherein theinput ring gear and the counter ring gear on the input shaft arefloatingly supported in the housing.
 7. (canceled)
 8. (canceled)
 9. Anangle drive according to claim 1 wherein the output shaft is supportedonce in the housing.
 10. An angle drive according to claim 1 wherein atleast one intermediate gearwheel is rotatably supported on a fixedhousing journal.
 11. An angle drive according to claim 1 wherein theinput ring gear and the counter ring gear are crown wheels and that theoutput gearwheel and the at least one intermediate gearwheel are spurgears with straight toothing or helical toothing.
 12. (canceled)
 13. Anangle drive according to claim 1 wherein a plug-in sleeve is arranged inthe journal end of the input shaft for connecting to an output shaft ofa differential.
 14. An angle drive according to claim 1 wherein thehousing comprises a spoke supporting a hub extending coaxially with thefirst axis (A₁) and wherein the input shaft is supported by the hub. 15.An angle drive according to claim 14 comprising two intermediate gearwheels running on respective rotary journals each of which is supportedat one end by the housing and at another end by the hub.
 16. An angledrive according to claim 1 wherein the housing comprises, in its inside,a carrier structure and wherein the angle drive comprises twointermediate gear wheels running on respective rotary journals each ofwhich is supported by the carrier structure.
 17. An angle drivecomprising: a housing; a hollow input shaft which is axially floatinglysupported in the housing and is positioned on a first axis (A₁); aninput ring gear fixed on the input shaft; an output shaft which issupported in the housing, and which carries an output gearwheel and ispositioned on a second axis (A₂) which intersects the first axis (A₁) ata right angle; a counter ring gear which is positioned on the inputshaft and which, with reference to the second axis (A₂), is arranged anddesigned symmetrically relative to the input ring gear; and twointermediate gearwheels each supported in the housing and arranged on anaxis (A₃, A₄) positioned radially relative to the first axis (A₁) and inthe same plane as, and forming identical pitch angles with, the secondaxis (A₂), each intermediate gearwheel having the same type of toothingas the output gearwheel; wherein the counter ring gear is supported soas to be independently rotatable relative to the input ring gear, andwherein the input ring gear and the counter ring gear are crown wheelswhich, via their respective teeth, simultaneously engage the outputgearwheel and each intermediate gearwheel, the output gearwheel and theintermediate gearwheels being spur gears with straight or helicaltoothing.
 18. An angle drive according to claim 17 wherein the housingcomprises a spoke supporting a hub extending coaxially with the firstaxis (A₁) and wherein the input shaft is supported by the hub.
 19. Anangle drive according to claim 18 wherein the intermediate gearwheelseach run on respective rotary journals supported at one end by thehousing and at another end by the hub.
 20. An angle drive according toclaim 17 wherein the housing comprises, on its inside, a carrierstructure and wherein the intermediate gearwheels each run on respectiverotary journals supported by the carrier structure.
 21. An angle drivecomprising: a housing; an input shaft which is supported in the housingand is positioned on a first axis (A₁); an input ring gear fixed on theinput shaft; an output shaft which is supported in the housing, andwhich carries an output gearwheel and is positioned on a second axis(A₂) which intersects the first axis (A₁) at a right angle; a counterring gear which is supported in the housing, which is positioned on theinput shaft and which, with reference to the second axis (A₂), isarranged and designed symmetrically relative to the input ring gear; andat least one intermediate gearwheel which is supported in the housing,which is arranged on an axis (A₃, A₄) positioned radially relative tothe first axis (A₁) and in the same plane with the second axis (A₂) andwhich is provided with the same type of toothing as the outputgearwheel; wherein the counter ring gear is supported so as to beindependently rotatable relative to the input ring gear, and wherein theinput ring gear and the counter ring gear, via their respective teeth,simultaneously engage the output gearwheel and the at least oneintermediate gearwheel, wherein the counter ring gear is supported onthe input shaft by a radial bearing; and wherein the counter ring gearis axially supported on the input shaft by an axial bearing.
 22. Anangle drive according to claim 21, wherein several intermediategearwheels, by way of respective radial axes (A₃, A₄), form identicalpitch angles with the second axis (A₂).
 23. An angle drive according toclaim 21 wherein the input shaft is a hollow shaft adapted to receive athrough-shaft.
 24. An angle drive according to claim 21 wherein theinput shaft is supported twice in the housing.
 25. An angle driveaccording to claim 21 wherein the input ring gear and the counter ringgear on the input shaft are floatingly supported in the housing.
 26. Anangle drive according to claim 21 wherein the output shaft is supportedonce in the housing.
 27. An angle drive according to claim 21 wherein atleast one intermediate gearwheel is rotatably supported on a fixedhousing journal.
 28. An angle drive according to claim 21 wherein theinput ring gear and the counter ring gear are crown wheels and that theoutput gearwheel and the at least one intermediate gearwheel are spurgears with straight toothing or helical toothing.
 29. An angle driveaccording to claim 21 wherein a plug-in sleeve is arranged in thejournal end of the input shaft for connecting to an output shaft of adifferential.
 30. An angle drive according to claim 21 wherein thehousing comprises a spoke supporting a hub extending coaxially with thefirst axis (A₁) and wherein the input shaft is supported by the hub. 31.An angle drive according to claim 30 comprising two intermediate gearwheels running on respective rotary journals each of which is supportedat one end by the housing and at another end by the hub.
 32. An angledrive according to claim 21 wherein the housing comprises, in itsinside, a carrier structure and wherein the angle drive comprises twointermediate gear wheels running on respective rotary journals each ofwhich is supported by the carrier structure.